Leo Satellite Mobile Communication System Switching Technology And Space Communication Protocol

Satellite mobile communication systems are parts of realizing global personal communications. Recently, LEO satellite mobile communication systems become one of the main research fields of satellite communication technologies. In the dissertation, it studies diversified handoff strategies in handoff technology of LEO satellite mobile communication systems, which are focused on combining handoff process with channel allocation and resource reservation. By the proper handoff algorithm, it will reduce the call blocking probability, enhance the resource utilization and get the better system performance. At the same time, using satellites to transfer TCP/IP data is the new direction of satellite communication, because of the rapid development of Internet services and the special technologies and application advantage of satellite communication. The dissertation does research on a normal space communication protocol-SCPS. SCPS is come into being by improved TCP/IP, the famous protocol in terrestrial networks. It is efficiently applied to space satellite channel, and realizes reliable data communication. Chapter 1 is the preface, which concisely introduces the development, status and perspective of the satellite communication, and the arrangement of this dissertation. Chapter 2 mainly studies diversified handoff strategies in handoff technology of only voice service LEO satellite mobile communication systems, and then raises a fair dynamic channel resevation scheme. This scheme resolves the fairness and priority problems of new call and handoff call. In addition, it adopts self-adjusting to be adaptive to varying traffic loads and makes the blocking probability smoother. The results by analysis and simulation in grade of service and channel utilization prove the better performance of this scheme. The trend of the wireless communication must be multimedia services, so it does research on handoff schemes for multi-service. Chapter 3 proposes a new handoff algorithm, the dynamic channel thresholds and preemptive priority scheme for integrated voice and data LEO satellite mobile communication systems. According to the queuing strategy and a Guard Channel scheme based on dynamic channel thresholds, this scheme reduces the blocking probability of all kinds of calls, moreover,...